Bushing structure



June 2, 1931. A. A. SKVORTZOFF BUSHING STRUCTURE Filed Dec. 14, 1928 INVENTOR fi/exanderfl &war/zo# ATTORNEY Patented June 2, 1931 ALEXANDER A; BKVOBTZOFF, OF SHABON,

PATENT' OFFICE;

PENNSYLVANIA, ASSIGNOB ro wEsriNG- HOUSE mCTRIC d; MANUFAC TUBDQ'G COMPANY, A. (DRPORATION OF PENNSYIF VAm BUSHING STBUCTUBE 4 'A lication med neeeme- 14, 1928. Serial Io. sac ,0131

My invention relates to electrical-bushing V structures and particularly to bushing structures of the hi h-voltage type.

An object of my invention is to provide a bushing of the above-indicated character that shall be tightly sealed against the passage' bf fluids, such as air, oil and any other medium which it is desired to use and which flows.

Another object of my invention is to proo vide a bushing that shall permit relative movement between sealed parts thereof without adversely eflt'ecting the seal between such parts. e

Another object of my invention is to provide a bushing structure that shall ermit the ready testing of the fluid-tight sea 'ng parts without materially altering the structure, as it would exist without the testing means.

A further object of my inventon is to provide.` a high-voltage-bushing structure that shall be simple and durable in construction, i economical to manufacture and eflective in its operation.. In electrical bushings, particularly those of the high-voltage type, it is desirable to have the same as nearly perfectly sealed as possible against the admission 'of moisture and the V egress of oil or other insulating fluid.

'Many suggested means, including screw clips, askets and other devices, have been emo e om ezdegree of success, but the problem is still of suflicient'importance to cause a great deal of constructive eflort to solve it completely not only from the standpoint of absolute fluid tightness, but also from .the vie oints of commercial and engineering expedency and economy.

It has -recently been suggested, in bushing structu'es embodying inorganic in'sulati'ng material, such as porcelain, to providea metalliclaze surface on a portion of'the porcelain, w ereby a substantially perfect hermetic seal may be eflected. However, this expedient has certain defects, as do most seals that have been heretofore sug ested. One of the objections to this expeent is the necessity for refirin the porcelain, after it has been Ori nally fied in the kil n, to provide the metallicglaze surface.

in -bushings of this character with It is my aim to provide a hermetically-tight seal that shall be substantially as rfect as one. emplo ing the metallic glaze a ove-mentioned an that shall have advantages over other expedients of the prior art.

Accordingly, in practicing my invention, I provide a bushin in which a flexible metallic member is so omogeneously sealed in position between the bushing conductors and a metal end cap therefor, and in which the metal end ca is so mechanically sealed'to the end of the tud stantially perfect seal in what is believed to he a more simple economical and expeditious manner than in an similar bushing structure heretofore emp oyed.

The single figure of the accompanying drawing is a side view, partially in elevation and partially in section, of a portion of a bushng structure constructed in accordance with m v invention; V

The evice comprises, in general',`a tubular dielectric member 2, a conductor 3 extending longitudinally therethroug 'a holdin member 4 on the member 2, a scaling as et 5, a cap or closure member 6 and a flexi l'e scaling elemeent 7 between the conductor 3 and the cap j e The dielectric member 2, onl the 'upper end of which is shown, is pre erably constructed of porcelain having a flat-plane outer surface 9 and annular surface-creepage flanges (not shown) distributed along its outer side, in a usual and well-known manner.

'The .conductor 3, which may be tubular or solid, as illustrated, and extended entirely through the lower part of the 'bushing structure (not shown) ,may also be provided, within the tubular member 2, with a condenser bushing of a well-known type. Also, a body 8 of oil or other insulating medium may be provided in the member 2. p

The holdin member 4, preferably of metal and of closed cop or ring-like character having tapped o enngs 12 about its outer end surface for t e reception of screw bolts 14 for holding the 6 in position is aiso preferably-displaced s ghtly inwardly from the end surface 9. The ring 4 may be Secured or ular member as to providea sub- -other suitable material,

bonded to the tubular member 2 in any manner, permanently and ti htly securing the ring in position, asby a dy of cement 15, alloy or other suitable means.

The sealing gasket 5, preferably of cork, hard rubber or similar yelding material, is also preferably initially treated with a sealing substanca, such as bakelite varnish or which is appled to both sides of the/gasket.

The cap 6, preferably of copper or brass, is of substantially flat-plane discoidal or ringlike character havin perimetral openings *16 for the reception o the bolts 14, a central opening 17, through which the conductor 3 loose'ly extends in, spaced relation thereto, and a radial opening or duct.18 having a removable closure cap member 19 at the outer end thereof.

The flexible sealing element 7, preferably of sheet material, such as copper or soft brass, is of substantially bell-'shape having its upper or smaller apertured end 20 sealed in position about the conductor '3, a's by a ring of solder 22, and its lower or mouth perimeter sealed to the cap 6 by a sealing ring 23, similar to the ring 22.

The above-described structure embodies a hermeticallytight seal between the conductor 3 and the cap 6, whereby the conductor may move either by thei-mal expansion 'of the parts or by mechanical strains relative to the cap and the parts therebeneath.

During ,assembly, the gasket 5 is placed in the positon shown, with the varnish thereon in wet or tacky condition. i The cap 6 is mounted in position and screwed down tightly, by means of the bolts 14, to compress the gaslt 5 and is held in position by lock washers The duet 18 is provided to permit the sealed parte to be tested in a sim le and expeditious manner by admitting uid, such as air, under pressure.

In the above-described structure, the parte are all of standard well-known materials and construction which are easily and economically manufactured. They ma also be readily and expedtiously assembl without special tools or extra equipment and' cooperate to provide an extremely effective structure.

While I have shown and described a particular form of my invention, changes may be eflected therein without departing from the spirit and s'cop thereof, as set orth in the appended claims. i

I claim as my invention:

1. A bushing congisin a dielectric tube, aholding member nde to, and around, said tube and displaced from an 'end thereof, a ring over said end having a radial duet, removable means for swlin said duet, a sealin gasket between said en and said ring,

` a con uctor extending through said ring in spaced relation thereto, a flem'ble sheet-masaid end, a sealing gasket between said end and said ring, a conductor extending through said ring in spaced' relation thereto, a flexible sheet-material bell surrounding said conductor over said ring having its smaller outer end intimately joined to sad conductor and its larger inner end intimately joined to said ring, and means for clamping said holding member relative to said ring to compress sai e gasket,

3. A bushing comprising a tubular insulating structure, a holding member Secured thereto adjacent to an end thereof, a ring over said end, a' sealing gasket between said end and said ring, a conductor extending loosely through said. ring, a flexible sheetmaterial element surrounding said conductor inintimate joinder to the same and to said ring, and means for clamping said holding member relative to said ring to compress said gasket. v

4. A bushing comprising a tubular insulating structure, a holding member Secured thereto, a ring over an end of said structure, a sealing gasketbetween said end and said ring, bonding material intimately joining and sealing said gasket to said end and to said ring, a conductor extending through said ring to permitmovement of the conductor relative thereto, flexible sealing means between the conductor and' the rin and means cooperating between saidhol mg member and' said ring to hold the same relative to each other;

5. A bushing comprising a tubular insulating structure, a ring over an end of said structure, means hermetically sealing said ring to said end, a 'conductor extending through, and ermitted to have movement relative to, sai ring, flexible means between, and intimately united-to both the conductor and the ring for hermetically sealing the same to each other, andmeans for securing the tubular structure and the ring to each other. f

6. A bushing comprising a tubular insulat- Ving structure, a removable ring over an end thereof, means hermetically sealing said ring to said end," a conductor extending through, and permitted to have movement' relatve to, said ring and an annular flexible metal element intimately united to the conductor and to the ring.

7. A bushing comprising a tubular insulating, structure, a conductor extendng longi- .tudnally through an end thereof and permitted to have movement relative thereto, and means for hermetically sealing the conductor to said structure, including an annular -flexible metal element int'mately united in sealed relation to the conductor and a removable metal ring-like element intimately united in sealed relation to said flexible element between said element and said end.

8. A bushing comprsing a tubular insulating structure, means for hermetically sealng an end thereof including a removable metal ring-like element sealed to said end and an annular flexible metab element intimately united and sealed, to said element, and a conductor dsposed longitudinally in said tubular structure and intimately connected, and sealed to said flexible element 9. In combinaton, a member having an opening therethrough, an apertured element disposed with its opening opposite the opening in said member, sealing means between said member and said element about an axis through said openings, a member e'xtending loosely through said openings, flexible scaling means about said axis intimately joined to said element and to said loosely-extending member, and means cooperating between said first member and said 'element to hold the same relative to each other.

In testimony whereof, I have hereunto subscribed my name this 16th day of November, 1928.

ALEXANDER A. SKVORTZOFF. 

